rust/src/librustc/front/core_inject.rs
Björn Steinbrink 1393c3a3f4 Use a specialized string interner to reduce the need for owned strings
&str can be turned into @~str on demand, using to_owned(), so for
strings, we can create a specialized interner that accepts &str for
intern() and find() but stores and returns @~str.
2013-05-09 14:40:19 +02:00

109 lines
3.4 KiB
Rust

// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use driver::session::Session;
use syntax::ast;
use syntax::attr;
use syntax::codemap;
use syntax::codemap::dummy_sp;
use syntax::fold;
static CORE_VERSION: &'static str = "0.7-pre";
pub fn maybe_inject_libcore_ref(sess: Session,
crate: @ast::crate) -> @ast::crate {
if use_core(crate) {
inject_libcore_ref(sess, crate)
} else {
crate
}
}
fn use_core(crate: @ast::crate) -> bool {
!attr::attrs_contains_name(crate.node.attrs, ~"no_core")
}
fn inject_libcore_ref(sess: Session,
crate: @ast::crate) -> @ast::crate {
fn spanned<T:Copy>(x: T) -> codemap::spanned<T> {
codemap::spanned { node: x, span: dummy_sp() }
}
let precursor = @fold::AstFoldFns {
fold_crate: |crate, span, fld| {
let n1 = sess.next_node_id();
let vi1 = @ast::view_item {
node: ast::view_item_extern_mod(
sess.ident_of("core"), ~[], n1),
attrs: ~[
spanned(ast::attribute_ {
style: ast::attr_inner,
value: @spanned(ast::meta_name_value(
@~"vers",
spanned(ast::lit_str(@CORE_VERSION.to_str()))
)),
is_sugared_doc: false
})
],
vis: ast::private,
span: dummy_sp()
};
let vis = vec::append(~[vi1], crate.module.view_items);
let mut new_module = ast::_mod {
view_items: vis,
../*bad*/copy crate.module
};
new_module = fld.fold_mod(&new_module);
// FIXME #2543: Bad copy.
let new_crate = ast::crate_ {
module: new_module,
..copy *crate
};
(new_crate, span)
},
fold_mod: |module, fld| {
let n2 = sess.next_node_id();
let prelude_path = @ast::Path {
span: dummy_sp(),
global: false,
idents: ~[
sess.ident_of("core"),
sess.ident_of("prelude")
],
rp: None,
types: ~[]
};
let vp = @spanned(ast::view_path_glob(prelude_path, n2));
let vi2 = @ast::view_item { node: ast::view_item_use(~[vp]),
attrs: ~[],
vis: ast::private,
span: dummy_sp() };
let vis = vec::append(~[vi2], module.view_items);
// FIXME #2543: Bad copy.
let new_module = ast::_mod {
view_items: vis,
..copy *module
};
fold::noop_fold_mod(&new_module, fld)
},
..*fold::default_ast_fold()
};
let fold = fold::make_fold(precursor);
@fold.fold_crate(crate)
}